Stellar merger model for gamma-ray burst

This sequence illustrates a model for the formation of a short-duration gamma-ray burst:

A pair of neutron stars in a binary system spiral together. Orbital momentum is dissipated through the release of gravity waves, which are tiny ripples in the fabric of space-time.

In the final milliseconds, as the two objects merge, they kick out highly radioactive material. This material heats up and expands, emitting a burst of light called a kilonova. An accompanying gamma-ray burst lasts just one-tenth of a second, but is 100 billion times brighter than the kilonova flash.